Textile machines



I. D. SLACK TEXTILE MACHINES 2 Sheets-Sheet 1 Dec. 9, 1969 Filed June 14, 1968 III Illll D. SLACK TEXTILE MACHINES Dec. 9, 1969 2 Sheets-Sheet 2 Filed June 14, 1968 United States Patent 3,482,387 TEXTILE MACHINES Ian David Slack, Drighlington, near Bradford, England, assignor to Plasticisers Limited, Drighlington, near Bradford, England Filed June 14, 1968, Ser. No. 737,168 Claims priority, application Great Britain, June 17, 1967, 28,025/ 67 Int. Cl. D01h 13/04 US. Cl. 57106 7 Claims ABSTRACT OF THE DISCLOSURE This invention provides means for assisting in the threading-up of ring twisting machines whereby the latter may be adapted to be operated in conjunction with textile filament producing equipment operating in a continuous manner. A hollow spindle is provided through which the leading end of the filament passes during threading-up of the machine. The filament is drawn into the spindle by suction or blown-in and waste storage means is provided at the other end of the spindle to c llect the filament drawn through the spindle.

This invention concerns textile machinery and in particular ring twister machines for twisting and winding yarn.

In a conventional ring twister machine untwisted yarn is supplied to the machine from a supply package for twisting and winding for example onto a tube. As one package of untwisted yarn is emptied so it can be replaced by a full package of untwisted yarn and at the same time the full tube of twisted yarn replaced by an empty tube. It will be appreciated that the tube could be replaced by a flanged bobbin. Although this arrangement is perfectly suitable to a production process where the yarn is produced in discrete lengths it is not readily adaptable to a continuous flow production line where the yarn is produced in a continuous length at high speed. Twisting the yarn has therefore been carried out as an independent process completely separate from the continuous production of the yarn since the time required to stop a twisting machine to remove and replace full and empty package results in an unacceptable pile-up of yarn. The problem becomes even more acute when a number of separate yarns are produced simultaneously and each requires to be twisted and wound separately.

It is therefore an object of the present invention to provide a twisting machine for imparting a twist to a yarn produced continuously, which at least in part overcomes the aforementioned problem.

In a conventional ring twisting machine the tube (or bobbin) is carried on and rotated by a spindle and the yarn passes through an eyelet (or lappet) mounted in axial alignment with the spindle. From the eyelet it is threaded through a traveller carried by a ring which surrounds the tube for winding around the tube. The ring is caused to traverse the length of the tube from one end to the other to thereby distribute the yarn as it is wound thereon, the rotation of the tube imparting twist into the yarn and the traveller causing the twisted yarn to be wound onto the tube.

According to one aspect of the present invention, in a ring twisting machine the spindle carrying the tube is hollow to receive the leading end of the yarn at least during threading up of the machine. Preferably fluid flow producing means are provided to induce a throughflow of fluid medium along the length of the hollow interior of the spindle to thereby convey the yarn through the spindle. The machine may additionally include yarn tensioning means arranged to act on the yarn after the lead- 3,482,387 Patented Dec. 9, 1969 ing end has passed through the hollow spindle to thereby increase the pull on the yarn over and above that exerted by the throughflow. Yarn storage means are convenientlv provided beyond the yarn tensioning means to collect the leading end of the yarn.

The throughflow of fluid medium may comprise a draught of air or gas and the machine accordingly can be provided with a suction producing device arranged at the end of the hollow spindle remote from the end through which the yarn enters the spindle and conveniently the suction producing device is located between said remote end of the spindle and the yarn tensioning means.

Alternatively and preferably the draught producing means comprises a blowing device arranged at or in front of the end of the hollow spindle through which the yarn enters, the device being arranged to direct a current of air or gas into that end of the hollow spindle. Conveniently the blowing device includes a number of nozzles which are arranged around the end of the hollow spindle and disposed so that the jets of air produced converge into the open end of the hollow spindle.

In practice a ring twisting machine would include a large number of spindles some of which are additional to requirements so. that as soon as one tube becomes filled with twisted yarn, the yarn can be transferred to an empty tube on one of the spare spindles and threaded-up in accordance with the invention. This allows the full tube spindle to be stopped and the full tube removed and replaced, by an empty tube for receiving yarn as soon as another tube becomes full.

From the foregoing it will be seen that the present in-- vention provides for the rapid threading-up of a ring twisting machine and accordingly provides means for assisting the threading-up of such a machine, comprising a hollow spindle on which the tube is mounted, fluid flow producing means for creating a through flow of fluid medium through the hollow interior of the spindle to thereby gather the leading end of the yarn and to cause it to enter the spindle and to convey the yarn therethrough for engagement by yarn tensioning means at the other end of the spindle. The threading device provided by the invention accordingly allows for continuous production of the yarn during threading-up of the twisting machine and prevents the pile-up of yarn which would otherwise occur.

The invention is of particular benefit when used in conjunction with a process for manufacturing synthetic fibre for example by means of an extrusion process.

The invention will now be described by way of eX- ample with reference to the accompanying drawings, in which:

FIG. 1 is a perspective view of a conventional ring twisting machine, and

FIG. 2, FIG. 3 and FIG. 4 are three similar views of a ring twisting machine according to the present invention and illustrate three stages in the threading-up operation of the machine.

In FIG. 1, which illustrates a conventional ring twisting machine, untwisted yarn is drawn from a bobbin 10 by a yarn feeding mechanism 12. The yarn is unwound from the bobbin 10 at a constant rate determined by the speed of rotation of the rollers in the yarn feeding mechanism 12 which comprises two driven rollers 14, 16 and a free running weighted roller 18. The feed roller are mounted vertically above a guide eyelet (or lappet) 20 which itself is arranged vertically above and in axial alignment with a vertical spindle 22. The spindle is rotated by means of a driving band or belt 24 which passes around a driving pulley 26 mounted on the spindle 22 which also carries a braking pulley 28 which cooperates with a brake shoe 30 to stop the spindle from 3 rotating. During braking the band or belt 24 is arranged to slip.

A hollow cylindrical take-up bobbin 32 is carried by the spindle 22 and the yarn after passing through the lappet 20, is guided onto the take-up bobbin 32 by a traveller 34 freely carried on a ring 36 arranged coaxially with the spindle 22. The traveller 34 is free to move around the ring 36 and at the same time, the ring 36 is arranged to traverse the length of the bobbin, reversing its direction as it reaches each end of the bobbin, so that the yarn is wound in layers on the bobbin as the latter rotates. For the sake of clarity, the traversing mechanism is not shown but the movement of the ring is merely indicated by means of the arrow 38.

The embodiment of the present invention illustrated in FIGS. 2, 3 and 4 is similar in principle to the arrangement illustrated in FIG. 1 and except where this embodiment diifers from the conventional arrangement, similar reference numerals have been used to denote corresponding parts which are similar. The essential difference between the conventional arrangement and the embodiment of FIGS. 2, 3 and 4 is the provision of a hollow spindle 40 in place of the solid spindle 22 of the arrangement of FIG. 1. By virtue of the hollow spindle 40 the yarn is conveyed axially through the twisting mechanism to emerge at the lower end of the spindle 40 where it passes between a pair of nip rollers 42, 44 which constitute a yarn tensioning and take-up device for feeding yarn into a yarn collecting bin or other suitable container (not shown). To assist in the rapid threading of the leading end of a yarn into and through the hollow spindle 40, a down-draught of air through the spindle is generated by an air ejector or vacuum pump 46, located at the lower end of the hollow spindle 40. The pump is not shown in any detail and it will be appreciated that any convenient form of draught producing means may be employed.

The threading-up operation is illustrated in three separate steps in FIGS. 2, 3 and 4 and the operation is as follows:

A spindle carrying an empty bobbin 32, with the spindle stationary, is positioned beneath the lappet and the leading end of a yarn to be twisted is fed through the lappet 20. It is then drawn into the upper end of the hollow interior of the spindle 40 and drawn down the spindle, by the down-draught of air created by the air ejector or vacuum pump 46, to emerge at the lower end of the spindle 40 and pass between the pair of nip rollers 42, 44.

With the brake still applied the yarn between the lappet 20 and the upper end of the hollow spindle is drawn out in the form of a loop and this is looped around the traveller 34 on the ring 36-as shown in FIG. 3.

The brake 30 is then released so that the spindle 40 and the bobbin 32 are caused to rotate. The yarn catches in a groove 48 formed in the upper end of the bobbin 32 and begins to be wound around the bobbin.

In order to ensure free rotation of the spindle and bobbin it is necessary to break the yarn between the spindle and nip rollers 42, 44. Although the continued rotation of the spindle and bobbin will eventually cause the yarn to fracture a guillotine or cutting edge is provided between the lower end of the spindle and the nip rollers 42, 44 to cut the yarn as soon as the yarn has begun to wrap around the tube. The guillotine is not shown in detail in the drawing but this conveniently comprises a knife edge (not shown) and a hook 50 which latter moves to engage and pull the yarn against the knife edge. I

Although feed rollers 14, 16 and 18 are shown for feeding the yarn to the lappet 20, these feed rollers are not required where. the extrusion process controls the linear speed of the yarn. In this situation the feed rollers can be replaced by a single guide roller.

Although in the described embodiment, the spindle is shown driven by a belt drive with friction brake, the

spindle may preferably be driven from an electric motor whose speed can be controlled to adjust the degree of twist imparted to the yarn.

In a machine employing a plurality of spindles, each spindle is preferably driven by a separate electric motor.

The vacuum pump/air ejector 46 can be replaced to advantage by a blowing device shown in dotted outline only in FIG. 2. The device comprises a discontinuous annular hollow shell of generally frusto-conical shape with its wide open end uppermost to receive the fiying/ leading end of yarn. The internal wall of the shell is stepped (not shown) and a plurality of downwardly directed nozzles are formed in the step to produce a converging downwardly directed air (or gas) stream which is directed into the upper end of the hollow spindle 40. The shell is discontinuous so as to enable it to be withdrawn when the yarn has passed therethrough and down the spindle and been engaged by the nip rollers 42, 44 and to assist in its movement from one position to another the device is conveniently mounted at the end of a flexible air line 62 for supplying compressed air thereto.

I claim:

1. A ring twisting machine comprising at least one rotatable spindle for supporting and rotating tubular yarn collecting means on which the twisted yarn is wound, said spindle being hollow to receive the leading end of the yarn at least during threading-up of the machine, fluid flow producing means to induce a throughflow of fluid medium along the length of the hollow interior of the spindle and thereby convey the yarn therethrough and yarn tensioning means to act on the yarn after it has passed through the spindle to increase the pull on the yarn over and above that exerted by the throughflow.

2. In a ring twisting machine as set forth in claim 1, yarn storage means beyond the yarn tensioning means to collect the yarn.

3. In a ring twisting machine as set forth in claim 1, said fluid flow producing means comprising means for establishing a gaseous draught through the hollow spindle.

4. In a ring twisting machine as set forth in claim 3, said gaseous draught producing means comprising suction means situated at the end of the spindle remote from the end through which the yarn enters.

5. In a ring twisting machine as set forth in claim 3, said gaseous draught producing means comprising blowing means situated at the end of the spindle through which the yarn enters. Y

6. In a ring twisting machine as set forth in claim 5, said blowing means comprising plural air outlet nozzles disposed around the end of the spindle and positioned to direct jets of air convergingly into the open end of the spindle.

7. In a ring twisting machine as set forth in claim 5, said blowing means being removable from the region adjacent the end of the spindle.

I Reference s Cited V UNITED STATES PATENTS 3,154,907 11/ 1964 Fischer 57-54 XR 3,257,083 6/1966 Furst 57-345 XR 3,333,407 8/1967 De Bruin et a1. 57-106 XR 3,385,045 5/ 196 8 Slowiak 57-345 XR 

